Mercury, from copper mining

Kot F, ShumiUn E, Rodriguez-Figueroa GM, Mirlean N (2009) Mercury dispersal to Arroyo and coastal sediments from abandoned copper mine operations, El Boleo, Baja California BuU Environ Contam Toxicol 82 20-25... 

In addition to the already mentioned role of chitosan and some of its derivatives in the treatment of waste waters in the food industry, these substrates have also been applied for the treatment of residual waters from the mining and chemical industries, usually contaminated with heavy metals like mercury, cadmium, lead and copper. These processes can be very efficient, even if the metal content in the effluents is as low as 10-50ppm [88],... 

The Lewis ENVIRO-CLEAN process removes and recovers metals such as chromium, copper, nickel, mercury, lead, zinc, iron, and cadmium and has effectively demonstrated that it can treat a matrix of multiple metals in a single stream with positive results. The process treats wastes from wood preserving, metal finishing, mining, surface and groundwaters. The two-step process uses granular-activated carbon and electrolytic metal recovery to yield a salable metallic by-product. 

The raw minerals mined from natural deposits comprise mixtures of different specific minerals. An early step in mineral processing is to use crushing and grinding to free these various minerals from each other. In addition, these same processes may be used to reduce the mineral particle sizes to make them suitable for a subsequent separation process. Non-ferrous metals such as copper, lead, zinc, nickel, cobalt, molybdenum, mercury, and antimony are typically produced from mineral ores containing these metals as sulfides (and sometimes as oxides, carbonates, or sulfates) [91,619,620], The respective metal sulfides are usually separated from the raw ores by flotation. Flotation processes are also used to concentrate non-metallic minerals used in other industries, such as calcium fluoride, barium sulfate, sodium and potassium chlorides, sulfur, coal, phosphates, alumina, silicates, and clays [91,619,621], Other examples are listed in Table 10.2, including the recovery of ink in paper recycling (which is discussed in Section 12.5.2), the recovery of bitumen from oil sands (which is discussed further in Section 11.3.2), and the removal of particulates and bacteria in water and wastewater treatment (which is discussed further in Section 9.4). 

Humans have been exposed more and more to metallic contaminants in the environment, mostly from the products of industry. There are three main sources of metals in the environment. The most obvious are the processes of extraction and purification mining, smelting, and refining. Another is the release of metals from fossil fuels (e.g., coal, oil), when these are burned. Cadmium, lead, mercury, nickel, vanadium, chromium, and copper are all present in these fuels, and considerable amounts enter the air or are deposited in ash. The third and most diverse source is the production and use of industrial products containing metals, which is increasing as new applications are found. The modem chemical industry, for example, uses many metals or metal compounds as catalysts metal compounds are used as stabilizers in the production of many plastics, and metals are added to lubricants, which then find their way into the environment.21... 

A principal environmental concern associated with mine wastes results from the oxidation of sulfide minerals within the waste materials and mine workings, and the transport and release of oxidation products. The principal sulfide minerals in mine wastes are pyrite and pyrrhotite, but others are susceptible to oxidation, releasing elements such as aluminum, arsenic, cadmium, cobalt, copper, mercury, nickel, lead, and zinc to the water flowing through the mine waste. 

Assuming that we continue to use metals at rates that are not proportional to their abundances, we can read directly from Fig. 10.5 those metals which are likely to be mined out first. The farther a metal plots from the dashed line, the earlier its demise. Metals apparently in trouble include such widely-used commodities as mercury, gold, silver, copper, and lead. By contrast with geochemically-scarce metals, all of the geochemically-abundant metals... 

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